Fundamental Scientific Investigations Research Articles

Induction of mutation in Neurospora Crassa using neem (Azadirachta Indica A. Juss) leaf extract

Filamentous fungus has been used as a significant source of biotechnological applications. Neurospora crassa, a type of red bread mold, has been well recognized as a model system in fundamental scientific investigations. It can be effectively utilized as a valuable resource for molecular tools, and many mutations are available. Furthermore, N. crassa exhibits rapid growth and has no harmful properties. These characteristics indicate a significant, although unexplored, capacity of this fungus for use in biotechnological endeavors. The present investigation aimed to induce morphological changes in the N. crassa wild type by employing leaf extracts derived from Azadirachta indica A. Juss. To determine the mutagenic and growth-inhibitory effects of A. indica leaves, morphological mutants were identified and individually examined. Six morphological mutants such as albino (al), cauliflower (clf), conidial band (co.band), ropy light (ro.lig), dirty (dir), and ropy (ro) were obtained from the conidia of the wild-type N. crassa Ema (5297) strain, treated with A. indica A. Juss. leaf extracts. These mutants were compared to the wild-type, natural form of the organism in terms of their morphology, radial growth, and reproduction ability. Apparent variations were observed when a comparative study of Ema and the selected morphological mutants was undertaken. Linkage among the selected mutants in their specific linkage group was determined. Ropy, dirty, and albino were all linked to leu-3 (linkage group I), conidial-band and ropy light to trp-1 (linkage group III), and cauliflower to trp-4 (linkage group VII). Complementation was not observed in similar morphological N. crassa mutants. Dhaka Univ. J. Biol. Sci. 33(1): 79-98, 2024 (January)

A framework for identifying the distribution of revitalization potential of idle rural residential land under rural revitalization

Idle rural residential land (IRRL) serves as a crucial resource for rural land utilization. Evaluating its potential for revitalization forms the foundational research in rural land consolidation. In the context of rural revitalization, quantitatively determining the potential to revitalize IRRL is a fundamental scientific investigation, requiring focus within the field of rural land sustainability research. In our study, we have developed a framework for identifying IRRL revitalization potential under rural revitalization, combining with the village development environment and self-characteristics of IRRL, and have proposed a classification method of IRRL revitalization types. Our results found a spatial mismatch between the IRRL revitalization potential and the external conditions of consolidation potential release. Compared with the IRRL consolidation potential based on spatial characteristics, the vitality of rural revitalization in Pinggu is small, which is manifested as low vitality of rural revitalization and surplus revitalization potential. Under rural revitalization, the IRRL revitalization potential in Pinggu is low. In the central agricultural and eastern semi-mountainous regions, IRRL plays a pivotal role in land reutilization within the context of rural revitalization. Moderate revitalization is the dominant revitalization type. The revitalization of IRRL in the central agricultural and eastern semi-mountainous regions plays a pivotal role in the reuse of residential land within rural revitalization. The prominent revitalization type is characterized as moderate revitalization. Considering the diversity of rural revitalization in Pinggu, the revitalization of IRRL should prioritize meeting a range of land usage needs within the rural revitalization context. Furthermore, it should capitalize on surplus potential through strategies like spatial transfer or retaining idle IRRL. Our research aims to foster a fresh perspective on the potential for revitalizing IRRL within the rural revitalization framework, emphasizing rural regional systems. This, in turn, can facilitate the harmonization of IRRL utilization with rural development, offering theoretical underpinning for human-land coordination and sustainable rural development in developing nations.

Boltzmann's equation at 150: Traditional and modern solution techniques for charged particles in neutral gases.

Seminal gas discharge experiments of the late 19th and early 20th centuries laid the foundations of modern physics, and the influence of this "golden era" continues to resonate well into the 21st century through modern technologies, medical applications, and fundamental scientific investigations. Key to this continuing success story has been the kinetic equation formulated by Ludwig Boltzmann in 1872, which provides the theoretical foundations necessary for analyzing such highly non-equilibrium situations. However, as discussed here, the full potential of Boltzmann's equation has been realized only in the past 50 years or so, with modern computing power and analytical techniques facilitating accurate solutions for various types of charged particles (ions, electrons, positrons, and muons) in gases. Our example of thermalization of electrons in xenon gas highlights the need for such accurate methods-the traditional Lorentz approximation is shown to be hopelessly inadequate. We then discuss the emerging role of Boltzmann's equation in determining cross sections by inverting measured swarm experiment transport coefficient data using machine learning with artificial neural networks.

Modern Tools for Increasing the Effectiveness of Distance Education in the Conditions of Digitalization

The current stage of developing digital technologies creates favorable conditions for intensifying the improvement of innovative distance education tools, the need for which is due to the intensification of the latest challenges and dangers. The research purpose is to substantiate the theoretical and applied principles of identifying the influence of modern tools for increasing the effectiveness of distance education in the conditions of digitalization. The methodological basis of the research includes general scientific and special methods of economic analysis and fundamental scientific investigation, in particular: system analysis, synthesis, scientific abstraction, comparison, analogy, statistical analysis, cluster analysis (k-means method), tabular, graphic, generalization, and systematization. The research results have revealed that the effectiveness of distance education in the conditions of digitalization significantly depends on the country’s development level. It has been found that three groups stand out among European countries, characterized by different levels of digitization and quality of distance education: highly developed countries (Denmark (MID: 0,90–1,00), Estonia (MID: 0,78–0,83), Ireland (MID: 0,76–0,80), Luxembourg (MID: 0,79–1,00), the Netherlands (MID: 0,91–0,95), Germany (MID: 0,81–0,88), Finland (MID: 0,88–0,90), Sweden (MID: 0,83–0,88); countries with an intermediate level of development (Bulgaria (MID: 0,58–0,62), Spain (MID: 0,62–0,64), Cyprus (MID: 0,64–0,67), Lithuania (MID: 0,63–0,66), Malta (MID: 0,64–0,70), Poland (MID: 0,54–0,64), Portugal (MID: 0,61–0,64), Romania (MID: 0,54–0,60), France (MID: 0,73–0,73), the Czech Republic (MID: 0,61–0,64), Slovenia (MID: 0,63–0,65), Azerbaijan (MID: 0,59–0,63) and countries with a low level of development (Greece (MID: 0,48–0,51), Italy (MID: 0,55–0,58), Latvia (MID: 0,55–0,59), Hungary (MID: 0,47–0,52), Slovakia (MID: 0,51–0,55), Croatia (MID: 0,46–0,50), Armenia (MID: 0,47–0,56), Georgia (MID: 0,48–0,50), Moldova (MID: 0,42–0,48), Ukraine (MID: 0,41–0,84). It has been proven that the most common digital tools for increasing the effectiveness of distance education are Viber (86,7%), an educational platform determined by the educational institution (60%), YouTube lessons (39,3%), Skype (13,3%) and Facebook (6%). It is proposed to increase the effectiveness of distance education by deepening society digitalization in countries with a low level of development and providing them with methodological assistance on the part of highly developed countries.

Self-Assembly of 2D Hybrid Double Perovskites on 3D Cs2 AgBiBr6 Crystals towards Ultrasensitive Detection of Weak Polarized Light.

We report the self-assembly of 2D double perovskite (BLA)2 CsAgBiBr7 (BLA=benzylammonium) on 3D Cs2 AgBiBr6 crystals, providing the first demonstration of polarization-sensitive photodetection using lead-free double perovskite heterocrystals (HCs). The (BLA)2 CsAgBiBr7 /Cs2 AgBiBr6 HC successfully combines the anisotropy of 2D double perovskites with the well-defined interface provided by heterogeneous integration. Driven by the built-in electric field in junction, photodetectors of HCs exhibit unique polarization dependence of zero-bias photocurrent with a large anisotropy ratio up to 9, which is 6 times amplified as compared to the pristine 2D (BLA)2 CsAgBiBr7 . More importantly, the present devices can remain polarization-sensitive with incident light intensity down to the nW cm-2 level. Our study on lead-free hybrid perovskite HCs marks a step toward establishing robust material foundations for fundamental scientific investigations and the development of optoelectronic devices.

Self‐Assembly of 2D Hybrid Double Perovskites on 3D Cs2AgBiBr6 Crystals towards Ultrasensitive Detection of Weak Polarized Light

AbstractWe report the self‐assembly of 2D double perovskite (BLA)2CsAgBiBr7 (BLA=benzylammonium) on 3D Cs2AgBiBr6 crystals, providing the first demonstration of polarization‐sensitive photodetection using lead‐free double perovskite heterocrystals (HCs). The (BLA)2CsAgBiBr7/Cs2AgBiBr6 HC successfully combines the anisotropy of 2D double perovskites with the well‐defined interface provided by heterogeneous integration. Driven by the built‐in electric field in junction, photodetectors of HCs exhibit unique polarization dependence of zero‐bias photocurrent with a large anisotropy ratio up to 9, which is 6 times amplified as compared to the pristine 2D (BLA)2CsAgBiBr7. More importantly, the present devices can remain polarization‐sensitive with incident light intensity down to the nW cm−2 level. Our study on lead‐free hybrid perovskite HCs marks a step toward establishing robust material foundations for fundamental scientific investigations and the development of optoelectronic devices.

Following the thread: Mytilus mussel byssus as an inspired multi-functional biomaterial

Over the last 15 years, the byssus of marine mussels (Mytilus spp.) has emerged as an important model system for the bio-inspired development and synthesis of advanced polymers and adhesives. But how did these seemingly inconsequential fibers that are routinely discarded in mussel hors d’oeuvres become the focus of intense international research. In the present review, we take a historical perspective to understand this phenomenon. Our purpose is not to review the sizeable literature of mussel-inspired materials, as there are numerous excellent reviews that cover this topic in great depth. Instead, we explore how the byssus became a magnet for bio-inspired materials science, with a focus on the specific breakthroughs in the understanding of composition, structure, function, and formation of the byssus achieved through fundamental scientific investigation. Extracted principles have led to bio-inspired design of novel materials with both biomedical and technical applications, including surgical adhesives, self-healing polymers, tunable hydrogels, and even actuated composites. Continued study into the byssus of Mytilid mussels and other species will provide a rich source of inspiration for years to come.

From Bedside to Bench: Reverse Engineering Medical Progress

From Bedside to Bench: Reverse Engineering Medical Progress

Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit

Entanglement is the quintessential quantum mechanical phenomenon understood to lie at the heart of future quantum technologies and the subject of fundamental scientific investigations. Mixture, resulting from noise, is often an unwanted result of interaction with an environment, but is also of fundamental interest, and is proposed to play a role in some biological processes. Here we report an integrated waveguide device that can generate and completely characterize pure two-photon states with any amount of entanglement and arbitrary single-photon states with any amount of mixture. The device consists of a reconfigurable integrated quantum photonic circuit with eight voltage controlled phase shifters. We demonstrate that for thousands of randomly chosen configurations the device performs with high fidelity. We generate maximally and non-maximally entangled states, violate a Bell-type inequality with a continuum of partially entangled states, and demonstrate generation of arbitrary one-qubit mixed states.

From Fundamental Polymerization Kinetics to Process Application—A Realistic Vision?

AbstractThis contribution presents a ramble through the past, inspecting the developments of fundamental scientific investigations into the elementary reaction steps of polymerizations. Often the question arises whether benefits from fundamental scientific investigation find their way into industrial practice and how these pay off in better understanding large‐scale processes. The high‐pressure ethene polymerization is the system of interest here because 1) it is a complex process with a world production of several million tons per year and 2) although dealing with system pressures up to 3000 bar is not an easy task, a long history—if not tradition—exists between the scientific efforts to improve the process and the research groups of Franck and Buback in Karlsruhe, Schönemann and Luft in Darmstadt, and later Buback in Göttingen. The scope of this discussion will range from non‐invasive on‐ and in‐line monitoring by spectroscopic methods up to process modeling by advanced kinetic models and their potential for explorative work.magnified image

Design, fabrication and implementation of a novel multi-parameter control microfluidic platform for three-dimensional cell culture and real-time imaging

New and more biologically relevant in vitro models are needed for use in drug development, regenerative medicine, and fundamental scientific investigation. While the importance of the extracellular microenvironment is clear, the ability to investigate the effects of physiologically relevant biophysical and biochemical factors is restricted in traditional cell culture platforms. Moreover, the versatility for multi-parameter manipulation, on a single platform, with the optical resolution to monitor the dynamics of individual cells or small population is lacking. Here we introduce a microfluidic platform for 3D cell culture in biologically derived or synthetic hydrogels with the capability to monitor cellular dynamics in response to changes in their microenvironment. Direct scaffold microinjection, was employed to incorporate 3D matrices into microfluidic devices. Our system geometry permits a unique window for studying directional migration, e.g. sprouting angiogenesis, since sprouts grow predominantly in the microscopic viewing plane. In this study, we demonstrate the ability to generate gradients (non-reactive solute), surface shear, interstitial flow, and image cells in situ. Three different capillary morphogenesis assays are demonstrated. Human adult dermal microvascular endothelial cells (HMVEC-ad) were maintained in culture for up to 7 days during which they formed open lumen-like structures which was confirmed with confocal microscopy and by perfusion with fluorescent microspheres. In the sprouting assay, time-lapse movies revealed cellular mechanisms and dynamics (filopodial projection/retraction, directional migration, cell division and lumen formation) during tip-cell invasion of underlying 3D matrix and subsequent lumen formation.

Structure and optical properties of silicon nanopowders

Nanopowders obtained in the work by evaporation of silicon ingot with a powerful electron beam with the energy of electrons ∼1.4 MeV in the atmosphere of Ar and N 2 is a perspective object as for the fundamental scientific investigations as for the practical application. These materials were investigated by transmission electron microscopy, Raman spectroscopy, photoluminescence spectroscopy, ultrasoft X-ray emission spectroscopy (USXES) and X-ray absorption near-edge structure (XANES). Results of investigations demonstrated that for a mean size of the particles of about 3–4 nm they consist of the ordered nanocrystalline silicon, amorphous silicon and silicon oxide. In this case photoluminescence can be observed in the visible spectral range with a peak at 2.1 eV. USXES spectra show that the particles of the powder consist of the phase with the ordered crystalline structure, amorphous silicon and silicon oxide. According to XANES data, the particles of nanopowders are covered with oxide layer with a thickness that is essentially greater than the natural silicon oxide.

Effect of Titanate-Based Surface on Hydrophilicity and Interlayer Spacing of Montmorillonite Clay for Polymer Nanocomposites

The fundamental scientific investigations on structure-property correlation of organo-clay are quite valuable in understanding the interface chemistry thus to design and engineer the most effective polymer-clay nanocomposites systems. Organo alkyl-titanate derivatives have been used as reagents for the surface modification of pristine montmorillonite clay platelets. Such surface modification is validated through coordinated characterization techniques that include X-ray photoelectron spectroscopy (XPS), contact angle measurements, X-ray diffraction (XRD) and thermo gravimetric analysis (TGA). By fine-tuning the surface characteristics (controlling the hydrophilicity); effective nanodispersion in polymers by intercalation or delamination can be accomplished. The titanate-coupling agent increased the water contact angle of the clay from 6 to 44 degrees denoting significant decrease in hydrophilicity. Similarly, XRD studies revealed the increased inter-gallery spacing from 9.8 to 12.7 A. The grafting of titanate modifier on to clay surface is quantified through XPS elemental analysis and co-related with TGA. This new surface-modification method provides an effective technique to convert the hydrophilic surface of the montmorillonite clay into organophillic for polymer-clay nanocomposites.

Representation of Knowledge in the Field of Fundamental Chemical Investigations. Dialogue Expert System DIACHEM

The paper develops the definite application of some artificial intelligence researches to the field of fundamental scientific investigations.

Biochemistry of trypanosomiasis and rational approaches to chemotherapy

The failure to develop any new drugs against trypanosomiasis over the last 20 years has encouraged fundamental scientific investigation into the biochemistry of these parasites in order to develop rational approaches to chemotherapy.

Necessity for Expanding Fundamental Scientific Investigations in Agriculture1

Agronomy JournalVolume 45, Issue 6 p. 225-227 Article Necessity for Expanding Fundamental Scientific Investigations in Agriculture1 Harold E. Myers, Harold E. Myers President, American Society of Agronomy, and Associate Director, Kansas Agricultural Experiment Station, Kansas State College.Search for more papers by this author Harold E. Myers, Harold E. Myers President, American Society of Agronomy, and Associate Director, Kansas Agricultural Experiment Station, Kansas State College.Search for more papers by this author First published: 01 June 1953 https://doi.org/10.2134/agronj1953.00021962004500060001xCitations: 1 1 Contribution No. 96, Office of Director, Kansas Agricultural Experiment Station. Address presented before Southern Section, American Society of Agronomy, February 9, 1953, New Orleans, La., on the occasion of the Golden Anniversary meeting of the Association of Southern Agricultural Workers. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume45, Issue6June 1953Pages 225-227 RelatedInformation

The Applied Physics Laboratory Research Center

The atomic bomb, the proximity fuze, and radar frequently have been cited as representing the three most outstanding advances in military science made by the U.S. during World War II. All, of course, are dramatic examples of so-called “practical” developments that would have been impossible without extensive prior fundamental scientific investigation carried out on an open-ended time scale in a research-for-its-own-sake environment. It is appropriate that the laboratory chiefly responsible for the wartime development of one member of the above triad should now be pioneering in the integration of applied and fundamental research within a single organization in a manner designed to produce optimum effectiveness for both. The establishment referred to is the Applied Physics Laboratory of The Johns Hopkins University, where the proximity fuze was developed. This laboratory, located in Silver Spring, Maryland, operates under a contract between the Bureau of Ordnance, U.S. Navy, and the University and for the past several years has been engaged principally in a guided-missile research and development program. An indication of its progress in this field is given by the fact that late in 1951 ground was broken in Pomona, California, for the construction for the Bureau of Ordnance of a multimillion dollar plant in which an APL-developed guided missile will be manufactured. The present discussion, however, is concerned only indirectly with the applied research and development to which most of APL's efforts are devoted. This article deals instead with the organization of and the thinking behind a particular division of the Laboratory called the Research Center.

SUBSURFACE CONSTITUTION OF BIKINI ATOLL AS INDICATED BY A SEISMIC-REFRACTION SURVEY*

As a part of the fundamental scientific investigation carried out in connection with the atomic bomb tests of 1946, a seismic refraction survey was made by Joint Task Force One to obtain information on the subsurface structure of Bikini Atoll. Naval depth charges were fired on the lagoon bottom along four lines extending across the atoll and the resulting seismic waves were picked up by water-coupled microphones near shore. A total of 126 charges were exploded in the survey. The time-distance curves indicate the existence of three zones with different sound velocity beneath the lagoon floor. For the uppermost layer, averaging about 2500 feet thick, the speed is 7000 ft/sec. Below this is a layer ranging from approximately 5000 to 10,000 feet in thickness with a seismic velocity of 11,000 ft/sec. Underlying the latter is a zone of undetermined thickness having a speed of 17,000 ft/sec. The recent boring, 2556 feet deep, on Bikini Island appears to confirm the conclusion reached from the seismic data alone that the uppermost zone consists of diverse calcareous materials such as are encountered on the sea floor within and around atolls at shallow depths,— i.e., a few hundred feet at the most. Results of a vertical velocity survey to 1800 feet in the same hole show a continuous transition from a velocity of 7000–11,000 ft/sec. It appears probable, therefore, that no essentially different rock materials enter into the composition of the atoll down to the top of the 17,000 ft/sec zone, and that the change in velocity is due mainly to progressive compaction and cementation of the calcareous sediments. In this case the 11,000 ft/sec layer indicated by the refraction data might consist of such sediments in a state of maximum cementation or of finer calcareous material, deposited in deeper water, that might have undergone greater compaction than the overlying coarser sediments. Parts of it, or even most of it, may be dolomitized; it might possibly consist mainly of pyroclastic sediments, although this seems less likely. Only a boring can provide a positive identification. The zone with a velocity of 17,000 ft/sec appears to represent the igneous basement. Its surface has considerable relief, the highest portion being near the center of the atoll about 7000 feet below sea level. From this summit a sharp nose plunges southeastward to the atoll9s edge, the greatest observed depth being about 13,000 feet. The seismic data suggest several possible histories of Bikini Atoll, but all require relative subsidence in the thousands of feet. If the material down to the 17,000 ft/sec zone is calcareous sand, the seismic evidence calls for a minimum of 7000 feet of subsidence. If a terrace on the surface of this zone at 13,000 feet is attributed to subaerial erosion, a minimum of 13,000 feet of subsidence is then required. If, on the other hand, the intermediate zone is identified as volcanic or pelagic material, it is still necessary to assume that there was at least 2000 feet of subsidence. Thus, for Bikini at least, the seismic results tend to favor the conception, first advanced in its simplest form by Darwin, that atolls are formed by long-continued subsidence of initial noncalcareous islands or shallow banks.

Cotton Research in East Africa

THE report of the administrative council of the Empire Cotton Growing Corporation submitted to the twenty-first annual general meeting on June 2 refers to a report by the Scientific Advisory Committee which outlines a scheme for the establishment by the Corporation of a Central Cotton Research Station in Uganda. Careful examination of the work being done by the present experiment stations has confirmed the view expressed in last year's report as to the value for the Empire of such a station in East Africa, at which fundamental scientific investigations could be carried out arising from practical problems that confront cotton-growing in those Dominions and Colonies in which the crop is cultivated on a commercial scale. The functions of such a station are defined as to carry out research on problems of cotton growing, especially on those of common interest to several territories. Such work should have a practical bearing on cotton production, and cotton should be treated as an element in peasant agriculture, compatible with food production, the prevention of erosion and the maintenance of soil fertility. Its functions would also include the co-ordination of certain activities of the Corporation's stations elsewhere in Africa, and if requested, of stations working on cotton and staffed by the Colonial Agricultural Service.